Cryopreservation Treatment

Egg Freezing and Cryopresrvation?

Cryopreservation of human embryos has been a routine procedure since the 1980’s. Standard techniques (which are still being wide utilized by most IVF centers) involve a slow chilling method that makes an attempt to forestall water content within the cells from forming ice crystals. Once crystals type, embryos become broken and lose their viability. Since 2006, we've got instead used an ultra-rapid chilling method referred to as vitrification. This innovative method chop-chop freezes the cells, thereby preventing living thing ice formation and avoiding cell harm. Vitrification involves freezing embryos or eggs in a very little quantity of a special resolution, before storing them in nitrogen liquid. Standard slow freezing yields a survival rate for human embryos of concerning 75 to 80%. In contrast, vitrification improves post-thaw embryo survival to >90%.

It is our preference to cryopreserve solely embryos that create it to the blastocyst stage. This can be primarily based upon our own recent analysis, revealed in Fertility and Sterility in 2007, that incontestible that embryos failing to develop to the blastocyst stage are nearly forever chromosomally abnormal. Several In Vitro Fertilization (IVF) programs still freeze embryos on day two or three when fertilization. Your medico ought to discuss this selection with you in order that your desires and goals are met. Several physicians believe this position of solely chilling solely “good quality” (grade one or 2) blastocysts (120-144 hours post egg retrieval) whereas others still encourage day-3 or earlier embryo freezing.

Since it takes many weeks to optimally perform complete CGH testing on eggs/embryos or blastocysts, it's out of the question to own the take a look at the result on the market within the time for a transfer of a contemporary blastocyst within the same cycle. By comparison, the partial genetic testing of PGD needs 2-3 days following the diagnostic assay, that permits contemporary embryos to be transferred within the same IVF cycle. so it's presently necessary to cryopreserve (vitrify) and store the blastocyst(s) for the future electronic transistor in a coming cycle (i.e. Staggered IVF). the security and effectiveness of the vitrification methodology currently makes it potential to transfer thawed blastocysts by electronic transistor with least concern for damaging an otherwise healthy embryo.

While the treating RE typically recommends once the embryos ought to be frozen, the ultimate call is absolutely up to the patient/couple. The RE ought to guide the method to best meet their expectations. at most of our centers, thawed embryos ar 1st allowed to develop to the blastocyst stage before being transferred to the female internal reproductive organ – no matter the stage at that the embryos were frozen. This suggests that once eggs are frozen at the earliest stage of development, they might be thawed and cultivated for many days. Those who attain the blastocyst stage of development are eligible for transfer to the female internal reproductive organ. In contrast, frozen blastocysts are thawed so transferred a couple of hours later.